Authoritarian UMNO reserved political power and other perks for the Muslim Malay majority, however, and stands accused of routinely trampling rights in silencing critics.

But voters, particularly from the economically powerful Chinese minority, have increasingly rebelled.

Last May's polls left UMNO clinging to power and conservatives resentful of Najib's reforms.

Right-wingers now appear intent on discarding multiculturalism to focus on the critical Malay Muslim vote, political experts believe, raising the specter of further polarization.

"This is significant as it could mean that [Najib's] vision of a unified, cohesive and inclusive plural society that was much touted in the 2013 elections is as good as thrown onto the back burner," Singapore's S Rajaratnam School of International Studies said in an analysis last week.

Seeking to shore up broad-based support, Najib came to power in 2009 promising to soften Malay chauvinism and protect democratic rights.

But after the polls he abandoned pledges – opposed by conservatives – to reform controversial policies granting Malays economic advantages.

The policies favoring Malays and other indigenous groups, who are collectively known as Bumiputra or "Sons of the soil", are blamed for shackling the economy and fuelling a "brain drain" overseas.

Human Rights Watch chastised the government this month over new legislation seen as oppressive, arrests of government critics and moves to curb civil society groups.

"The [2013] election was followed by a significant deterioration in human rights and the apparent abrupt end to Prime Minister Najib's oft-touted reform agenda," it said.

Meanwhile, influential Muslim groups allied to UMNO that were long leashed by the party have become more assertive, unsettling non-Muslims with calls for a more "Islamic" Malaysia.

"There are people who want to change the identity of Malaysia, which is based on Islam, Muslim and Malay supremacy. They want to change it to civil and secular society," fretted Abdullah Zaik Abdul Rahman, head of NGO Malaysia Muslim Solidarity.

"These are the real threats to Muslims in Malaysia."

Professed "moderate" Najib, 60, has drawn flak for not stepping in forcefully to calm things, particularly in the "Allah" row.

Conservative Muslims are demanding Malay-speaking Christians stop using "Allah" to refer to the Christian creator. The row has seen Bibles seized by Islamic authorities, a leading Catholic priest probed for sedition and Muslim protests.

"Najib seems unable to do anything. It's almost like Ibrahim Ali is running the country," said Wan Saiful of IDEAS, referring to the firebrand leader of a Malay-supremacy group who has previously threatened to burn Bibles.

With fresh elections due by 2018, UMNO conservatives are calling for a return to the days of premier Mahathir Mohamad, who ruled with an iron fist from 1981 to 2003.

Mahathir, 88, who led a campaign to drive out Najib's predecessor, has criticized the premier's reforms, sparking speculation Najib could be replaced.

"Time is running out" for progressives to take control, Lim Teck Ghee, CEO of Malaysia's Centre for Policy Initiatives, said in an analysis entitled "Can Malaysia step back from the brink?"

More likely is "a sharper turn towards an Islamic conservative future; or a retreat to emergency rule in which UMNO-led right wingers, and other powerful stake players including the [Malay] monarchy... make a bid for, and successfully seize power", he said. AFP

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